DOCSLIB.ORG

Paramecium (Protist)

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Paramecium (Protist) Paramecium (Protist) Paramecium is a group of unicellular ciliate protozoa ranging from 50 to 350 μm in length. Simple cilia cover the body, which allow the cell to move with a synchronous motion ­ like a caterpillar. There is also a deep oral groove containing inconspicuous tongue­like compound oral cilia (as found in other peniculids) used to draw food inside. They generally feed on bacteria and other small cells, making them heterotrophs. Osmoregulation is carried out by a pair of contractile vacuoles, which actively expel water from the cell absorbed by osmosis from their surroundings. They are relatively large protists and can easily be seen with a medium­power microscope. 1 Biology Thursday/Friday September 6/7, 2012 1. Organism of the Day: Paramecium 2. Review Homework ­10 3. Notes ­10 4. Field Trip ­50 5. Pond Water Lab ­30 Announcements Pay the $15 class fee to Sarah Spray in the Main office. Due Today: Finish defining life and 5 Kingdom Basics. Due Monday: Pond Water Lab and read 3.1 from ML Biology textbook and answer questions 1 ­ 3. 2 Review Homework 3 Ecology Key Terms Food Chain: Is a series of steps in which organisms transfer energy by eating and being eaten. Food Web: In an ecosystem feeding is more complicated because one animal can often eat more than one kind of food. 4 5 Ecology Key Terms Draw pictures:) Ecology: Is the scientific study of interactions among organisms and between organisms and their physical environment. Interactions within the biosphere produce a web of interdependence between organisms. Biotic Factors: The biological influences on organisms are called biotic factors. In other words, a biotic factor is any living part of the environment with which an organism might interact, including animals, plants, mushrooms, and bacteria. Think: what could be a biotic factor for the wolves in Yellowstone? 6 Abiotic Factors: Physical components of an ecosystem. More specifically, an abiotic factor is any nonliving part of the environment, such as sunlight, heat, percipitation, humidity, wind, soil type, etc. Example: A bullfrog could be affected by abiotic factors such as water availability, temperature, and humidity. Think: what could be an abiotic factor for the wolves in Yellowstone? Autotrophs (Primary Producers): Use energy from the sun (or chemical energy source) to produce chemical energy via photosynthesis. This energy is often stored in sugars and is made available to other organisms when eaten. Heterotrophs (Consumers): Must acquire energy by eating other organisms. Can be classified as carnivores, herbivores, scavengers, omnivores, decomposers, and detritivores. Think: How should a wolf be classified? 7 Ecology: Study of how organisms interact with each other and their environment. 1. Organisms occupy a specific niche ­ ex. Paramecium 2. Biotic and abiotic factors ­ ex. Pond 3. Nutrient cycling ­ ex. Pond 4. Interactions between organisms ­ Food chain 5. Changes occur ­Season ­Succession 8 Field trip guidelines Bring a notebook, pencil/pen ­individual Bring GLX interface with temperature probe, a yardstick as a group Walk as a class to Sportsman Club Pond. Record notes on the following: 1. Number and types of organisms 2. Interactions between organisms that you SEE! 3. Interactions between organisms and their environment 4. Record Quantitative data via observations and GLX probe. 5. Record Qualitative data via obseravtions. 6. Think about how this environment changes with the seasons! 7. Be responsible. 8. Have FUN exploring nature! 9 Period 3 Group 1 Group 5 Matthew D Bowman Jessica C Markowitz Casey A Brink Cristen H McCann Ana M Bucy Bryce A Miller Sophie K Carson Talbot N Miller Group 2 Group 6 Cassandra R Christean Truman H Miller Kamryn H Coryell Hannah M Pratt Lauren M Cummings Albert C Ragsdale Connor W Dalton Cole K Schardein Group 3 Group 7 Carter J Daniels Conner T Vacca Alyssa L James Christian M VanWagner Ciaran M Krantz Lauren T Vchulek Elizabeth N Viele Group 4 Group 8 Caroline T Lant Karen E Ware Weappa­ Alexander W Larsen Finnian A Mickelson Joseph S Lee Lindsay B Wienkers Britt P Lindquist 10 Period 5 Group 1 Group 5 Natalie H Allen Chase E Lehotsky Tara N Bieber Ciana L Maasen Lucas Burzycki Sienna M Mander Myron E Butler Glynnis R Marcus Group 2 Group 6 Aidan Z Carlisle Angeline P Mead Quinn H Dassel Morgan L Merillat Lucinda M DeBolt Gregory G Millican Zachary M Dinniman Erik P Nimb Group 3 Group 7 Forrest L Englin Sonia K Olson Isabella A Frawley Avery Schuelke Rory L Frieda Georgia R Seltzer Jake M Sullivan Group 4 Group 8 Oliver Godfrey Shelby W Sundquist Jade C Greer Parker R Taylor Keivan Kehlhofer Hayden S Tutty Kailyn J Wise 11 Period 6 Group 1 Group 5 Nathan A Agne Shaine E McMahon Natalie T Beatie Alexandra R McWilliams Madeleine J Cole Caitlyn P Munter Annie E Comstock Natalya C Niehaus Group 2 Group 6 Elanor S Davidson Larissa N Nowjack Lars N Erickson Caleb J Olalia David Goon Klaudia Prodani Bryce T Hamilton Garret W Riely Group 3 Group 7 Robert M Hobbs Mira I Rosenkotz Isaac J Holloway Blake A Swanson Ryan B Ieropoli Brandon J Swindle Reed T Thomas Group 4 Group 8 Abigail L Leigh Kathryn P Tibbens Cole A Magrini Chaney A Weaver Erin A McGee Lucas F Weyand Andrew B Yalung 12 13 Name ________________________ Group # ______ Period ______ Date _______________ _____/14 Points PondWaterLab This investigation is designed to help you practice making observations, focusing a light microscope on living organisms, preparing wet mount slides, and drawing aquatic organisms found in Sportsman Club Pond water. Take special note of the characteristic of life. Study and know the part of the microscope (see your diagram). Quiz your lab partners on the microscope parts. 1. Qualitative data: Describe what you see at Sportsman Club Pond. What color is the pond water? What do you see growing in and around the pond? What do you hear? What do you smell? ________________________________________________________________________________________ ________________________________________________________________________________________ ________________________________________________________________________________________ What are other qualitative observations we can make? 2. Quantitative data: Use your GLX probe to measure the pH and the temperature of the water: pH ___________ Temperature ______________. 3. Magnification: Knowing that the power of the eyepiece is _________, determine the following magnifications: Low power = _______ x _______ = _______ Medium power = _______ x _______ = _______ High power = _______ x _______ = _______ 4. Wet mount: Be sure that the water is contained under the cover slip (none is slopping out) and that there are as few bubbles as possible. Avoid large organisms at this time. Proceed to the pond water chart (see reverse) and draw 3 pictures in the circles: one at low, one at medium, and the last at high magnification. Repeat again with a different sample and label as wet mount slides. 5. Depression slide: Find a larger organism and prepare a depression slide mount and draw a detailed picture of your organism as you did with the wet mount. 6. Hypothesis : How do you think the pond will look in the winter? What differences/similarities would you see in the samples you examined through the microscope? Be specific and explain your reasoning. ________________________________________________________________________________________ ________________________________________________________________________________________ ________________________________________________________________________________________ 14 Name ________________________ Group # ______ Period ______ Date _______________ NOTE: In sketching organisms, be as detailed as possible. Scientific drawings use pencil, ruler, label features, the power of magnification, and include a title and the scale. 15 Exit Question If the eyepiece magnification is 10x and the total magnification is 500x, then what is the magnification of the objective lense? Reminders Pay the $15 class fee to Sarah Spray in the Main office. Due Monday: Pond Water Lab and read 3.1 from ML Biology textbook and answer questions 1 ­ 3. Periods 3/5: Please stack chairs on your way out. 16 Attachments Web Quest Mental Health.doc.
Load more

Recommended publications
  • Basal Body Structure and Composition in the Apicomplexans Toxoplasma and Plasmodium Maria E
    Francia et al. Cilia (2016) 5:3 DOI 10.1186/s13630-016-0025-5 Cilia REVIEW Open Access Basal body structure and composition in the apicomplexans Toxoplasma and Plasmodium Maria E. Francia1* , Jean‑Francois Dubremetz2 and Naomi S. Morrissette3 Abstract The phylum Apicomplexa encompasses numerous important human and animal disease-causing parasites, includ‑ ing the Plasmodium species, and Toxoplasma gondii, causative agents of malaria and toxoplasmosis, respectively. Apicomplexans proliferate by asexual replication and can also undergo sexual recombination. Most life cycle stages of the parasite lack flagella; these structures only appear on male gametes. Although male gametes (microgametes) assemble a typical 9 2 axoneme, the structure of the templating basal body is poorly defined. Moreover, the rela‑ tionship between asexual+ stage centrioles and microgamete basal bodies remains unclear. While asexual stages of Plasmodium lack defined centriole structures, the asexual stages of Toxoplasma and closely related coccidian api‑ complexans contain centrioles that consist of nine singlet microtubules and a central tubule. There are relatively few ultra-structural images of Toxoplasma microgametes, which only develop in cat intestinal epithelium. Only a subset of these include sections through the basal body: to date, none have unambiguously captured organization of the basal body structure. Moreover, it is unclear whether this basal body is derived from pre-existing asexual stage centrioles or is synthesized de novo. Basal bodies in Plasmodium microgametes are thought to be synthesized de novo, and their assembly remains ill-defined. Apicomplexan genomes harbor genes encoding δ- and ε-tubulin homologs, potentially enabling these parasites to assemble a typical triplet basal body structure.
    [Show full text]
  • Molecular Data and the Evolutionary History of Dinoflagellates by Juan Fernando Saldarriaga Echavarria Diplom, Ruprecht-Karls-Un
    Molecular data and the evolutionary history of dinoflagellates by Juan Fernando Saldarriaga Echavarria Diplom, Ruprecht-Karls-Universitat Heidelberg, 1993 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in THE FACULTY OF GRADUATE STUDIES Department of Botany We accept this thesis as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA November 2003 © Juan Fernando Saldarriaga Echavarria, 2003 ABSTRACT New sequences of ribosomal and protein genes were combined with available morphological and paleontological data to produce a phylogenetic framework for dinoflagellates. The evolutionary history of some of the major morphological features of the group was then investigated in the light of that framework. Phylogenetic trees of dinoflagellates based on the small subunit ribosomal RNA gene (SSU) are generally poorly resolved but include many well- supported clades, and while combined analyses of SSU and LSU (large subunit ribosomal RNA) improve the support for several nodes, they are still generally unsatisfactory. Protein-gene based trees lack the degree of species representation necessary for meaningful in-group phylogenetic analyses, but do provide important insights to the phylogenetic position of dinoflagellates as a whole and on the identity of their close relatives. Molecular data agree with paleontology in suggesting an early evolutionary radiation of the group, but whereas paleontological data include only taxa with fossilizable cysts, the new data examined here establish that this radiation event included all dinokaryotic lineages, including athecate forms. Plastids were lost and replaced many times in dinoflagellates, a situation entirely unique for this group. Histones could well have been lost earlier in the lineage than previously assumed.
    [Show full text]
  • Gaits in Paramecium Escape
    Transitions between three swimming gaits in Paramecium escape Amandine Hamela, Cathy Fischb, Laurent Combettesc,d, Pascale Dupuis-Williamsb,e, and Charles N. Barouda,1 aLadHyX and Department of Mechanics, Ecole Polytechnique, Centre National de la Recherche Scientifique, 91128 Palaiseau cedex, France; bActions Thématiques Incitatives de Genopole® Centriole and Associated Pathologies, Institut National de la Santé et de la Recherche Médicale Unité-Université d’Evry-Val-d’Essonne Unité U829, Université Evry-Val d'Essonne, Bâtiment Maupertuis, Rue du Père André Jarlan, 91025 Evry, France; cInstitut National de la Santé et de la Recherche Médicale Unité UMRS-757, Bâtiment 443, 91405 Orsay, France; dSignalisation Calcique et Interactions Cellulaires dans le Foie, Université de Paris-Sud, Bâtiment 443, 91405 Orsay, France; and eEcole Supérieure de Physique et de Chimie Industrielles ParisTech, 10 rue Vauquelin, 75005 Paris, France Edited* by Harry L. Swinney, University of Texas at Austin, Austin, TX, and approved March 8, 2011 (received for review November 10, 2010) Paramecium and other protists are able to swim at velocities reach- or in the switching between the different swimming behaviors ing several times their body size per second by beating their cilia (11, 13–17). in an organized fashion. The cilia beat in an asymmetric stroke, Below we show that Paramecium may also use an alternative to which breaks the time reversal symmetry of small scale flows. Here cilia to propel itself away from danger, which is based on tricho- we show that Paramecium uses three different swimming gaits to cyst extrusion. Trichocysts are exocytotic organelles, which are escape from an aggression, applied in the form of a focused laser regularly distributed along the plasma membrane in Paramecium heating.
    [Show full text]
  • CH28 PROTISTS.Pptx
    9/29/14 Biosc 41 Announcements 9/29 Review: History of Life v Quick review followed by lecture quiz (history & v How long ago is Earth thought to have formed? phylogeny) v What is thought to have been the first genetic material? v Lecture: Protists v Are we tetrapods? v Lab: Protozoa (animal-like protists) v Most atmospheric oxygen comes from photosynthesis v Lab exam 1 is Wed! (does not cover today’s lab) § Since many of the first organisms were photosynthetic (i.e. cyanobacteria), a LOT of excess oxygen accumulated (O2 revolution) § Some organisms adapted to use it (aerobic respiration) Review: History of Life Review: Phylogeny v Which organelles are thought to have originated as v Homology is similarity due to shared ancestry endosymbionts? v Analogy is similarity due to convergent evolution v During what event did fossils resembling modern taxa suddenly appear en masse? v A valid clade is monophyletic, meaning it consists of the ancestor taxon and all its descendants v How many mass extinctions seem to have occurred during v A paraphyletic grouping consists of an ancestral species and Earth’s history? Describe one? some, but not all, of the descendants v When is adaptive radiation likely to occur? v A polyphyletic grouping includes distantly related species but does not include their most recent common ancestor v Maximum parsimony assumes the tree requiring the fewest evolutionary events is most likely Quiz 3 (History and Phylogeny) BIOSC 041 1. How long ago is Earth thought to have formed? 2. Why might many organisms have evolved to use aerobic respiration? PROTISTS! Reference: Chapter 28 3.
    [Show full text]
  • Diversity of Life Paramecia—Paramecium Caudatum
    Used in: Diversity of Life Paramecia—Paramecium caudatum Background. Paramecia are single-celled ciliated protists found in freshwater ponds. They feed on microorganisms such as bacteria, algae, and yeasts, sweeping the food down the oral groove, into the mouth. Their movement is characterized by whiplike movement of the cilia, small hair-like projections that are arranged along the outside of their bodies. They spiral through the water until running into an obstacle, at which point the cilia "reverse course" so the paramecium can swim backwards and try again. Paramecia have two nuclei and reproduce asexually, by binary fission. A paramecium can also exchange genetic material with another via the process of conjugation. Acquiring paramecia. You can purchase Paramecium caudatum from Delta Education or a biological supply house. This species is a classic classroom organism, hardy and large enough for students to easily observe using a light microscope. Purchase enough to "spike" a sample of water that students will use for preparing slides of elodea leaves and to use in Part 2 of Investigation 3 when students will focus specifically on study of the organism itself. What to do when they arrive. Open the shipping container, remove the culture jar, and loosen the lid on the jar. Aerate the culture using the pipette supplied, bubbling air through the water. Repeat several times to oxygenate the water. After about 15 minutes, use a dropper or the pipette to obtain organisms, gathering them from around the barley (or other food source). Prepare a wet-mount slide and look for paramecia using a microscope.
    [Show full text]
  • Electrical Responses of the Carnivorous Ciliate Didinium Nasutum in Relation to Discharge of the Extrusive Organelles
    J. exp. Biol. 119, 211-224 (1985) 211 Printed in Great Britain © The Company of Biologists Limited 1985 ELECTRICAL RESPONSES OF THE CARNIVOROUS CILIATE DIDINIUM NASUTUM IN RELATION TO DISCHARGE OF THE EXTRUSIVE ORGANELLES BY RITSUO HARA, HIROSHI ASAI Department of Physics, Waseda University, Tokyo 160, Japan AND YUTAKA NAITOH Institute of Biological Sciences, University ofTsukuba, Ibaraki 305, Japan Accepted 28 May 1985 SUMMARY 1. The carnivorous ciliate Didinium nasutum discharged its extrusive organelles when a strong inward current was injected into the cell in the presence of external Ca2+ ions. 2. In the absence of external Ca2+ ions, the strong inward current produced fusion of the apex membrane of the proboscis. 3. External application of Ca2+ ions after the fusion of the apex mem- brane produced discharge of the organelles. 4. An increase in Ca2"1" concentration around the organelles seems to cause discharge of the organelles. 5. Ca2+ concentration threshold for the discharge of the pexicysts seems to be lower than that for the toxicysts. 6. External Ca2+ ions were not necessary for discharge of the organelles upon contact with Paramecium. 7. Chemical interaction of the apex membrane with Paramecium mem- brane may cause intracellular release of Ca2+ ions from hypothetical Ca2+ storage sites around the organelles. 8. A small hyperpolarizing response seen before the discharge upon con- tact with Paramecium seems to correlate with the chemical interaction, 9. The depolarizing spike response associated with discharge of the organelles is caused by the depolarizing mechanoreceptor potential evoked by mechanical stimulation of the proboscis membrane by the discharging organelles.
    [Show full text]
  • Unicellular Eukaryotes As Models in Cell and Molecular Biology
    Unicellular Eukaryotes as Models in Cell and Molecular Biology: Critical Appraisal of Their Past and Future Value Martin Simon*, Helmut Plattner†,1 *Molecular Cellular Dynamics, Centre of Human and Molecular Biology, Saarland University, Saarbru¨cken, Germany †Faculty of Biology, University of Konstanz, Konstanz, Germany 1Corresponding author: e-mail address: [email protected] Contents 1. Introduction 142 2. What is Special About Unicellular Models 143 2.1 Unicellular models 144 2.2 Unicellular models: Examples, pitfals, and perspectives 148 3. Unicellular Models for Organelle Biogenesis 151 3.1 Biogenesis of mitochondria in yeast 152 3.2 Biogenesis of secretory organelles, cilia, and flagella 152 3.3 Phagocytotic pathway 153 3.4 Qualifying for model system by precise timing 155 3.5 Free-living forms as models for pathogenic forms 157 4. Models for Epigenetic Phenomena 158 4.1 Epigenetic phenomena from molecules to ultrastructure 161 4.2 Models for RNA-mediated epigenetic phenomena 163 4.3 Excision of IESs during macronuclear development: scnRNA model 170 4.4 Maternal RNA controlling DNA copy number 172 4.5 Maternal RNA matrices providing template for DNA unscrambling in Oxytricha 172 4.6 Impact of epigenetic studies with unicellular models 173 5. Exploring Potential of New Model Systems 175 5.1 Human diseases as new models 175 5.2 Protozoan models: Once highly qualified Now disqualified? 178 5.3 Boon and bane of genome size: Small versus large 179 5.4 Birth and death of nuclei, rather than of cells 183 5.5 Special aspects 184 6. Epilogue 185 Acknowledgment 186 References 186 141 142 Abstract Unicellular eukaryotes have been appreciated as model systems for the analysis of cru- cial questions in cell and molecular biology.
    [Show full text]
  • Chapter 16 Outline
    CHAPTER 16 Microbial Life: Prokaryotes and Protists Chapter Objectives Prokaryotes 16.1 Describe the diversity, abundance, and importance of prokaryotic life. 16.2 Compare the different shapes, cell walls, and projections of prokaryotes. 16.3 Explain how bacteria can evolve quickly and how bacteria can survive stressful environments. 16.4 Describe the types of nutritional diversity found in prokaryotes. 16.5 Explain why biofilms are unique and potentially dangerous to human health. 16.6 Explain how prokaryotes are employed to address the needs of human society. 16.7 Compare the three domains of life based on differences in cellular and biochemical traits. 16.8 Describe the diverse types of Archaea living in extreme and more moderate environments. 16.9 Distinguish between the five subgroups of the domain Bacteria, noting the particular structure, special features, and habitats of each group. 16.10 Describe some of the diseases associated with bacteria. Distinguish between exotoxins and en- dotoxins, noting examples of each. 16.11 Describe the four parts of Koch’s postulates. Explain how Marshall was able to demonstrate that the bacterium Helicobacter pylori can cause gastritis. Protists 16.12 Describe the basic types of protists. Explain why biologists currently think that they represent many clades. 16.13 Explain how primary endosymbiosis and secondary endosymbiosis led to further cellular diversity. 16.14 Describe and compare the groups that together form the supergroup SAR. 16.15 Explain how cultured algae may be used as renewable fuels and the current challenges that re- main. 16.16–16.18 Describe and distinguish between the Excavata, Unikonta, and Archaeplastida groups.
    [Show full text]
  • Eukarya Is Now Divided Into 4 Supergroups, Excavata, SAR Clade, Archaeplastida and Unikonta
    Eukarya is now divided into 4 supergroups, Excavata, SAR Clade, Archaeplastida and Unikonta. It replaces the earlier 5-kingdom classification of Monera – all prokaryotes, Protista – early eukaryotes and 3 multicellular kingdoms Plants, Fungi and Animals. Kingdom monera is replaced by 2 new domains Bacteria and Archaea. The classification of domain Eukarya is going on. Molecular data has broken the boundaries between protista and 3 multicellular kingdoms. Eukarya is likely to get more than 20 kingdoms but none of them is protista. Protists: of past are separated into 7 new groups that also have plants, fungi and animals. 1. Excavata 2. Stramenopiles 3. Alveolata 4. Rhizaria 5. Archaeplastida, also has plants 6. Ameobozoans 7. Opisthokonts, also has fungi and animals Protists were first eukaryotes to evolve. Protists include unicellular eukaryotes and their simple multicellular relatives. The latter are filamentous or colonial. Mitosis, Meiosis and sexual reproduction arose for the first time in this kingdom. All the organelles of plants, fungi and animals arose in this kingdom. Protists also possess many unique organelles not found anywhere else in the 3 domains. Like the 3 higher kingdoms the Protists are photosynthetic (like plants) or heterotrophic absorptive (like fungi) or heterotrophic Ingestive (like animals). Excavata: is a clade, some have excavated groove on side of body, reduced or modified mitochondria and unique flagella. Taxons include Diplomonads, Parabasalids and Eugleonozoans (kinetoplastids and euglenoids). a) Diplomonads: reduced mitochondria, called mitosomes which cannot use oxygen, therefore, diplomonads are anaerobic. Giardia intestinalis lives in intestines of mammals. It has 2 similar nuclei and several flagella. It causes abdominal cramps and diarrhea in humans.
    [Show full text]
  • Exploring Unique Aspects of Apicomplexan Cell Biology Using Molecular Genetic and Small Molecule Approaches Whittney Dotzler Barkhuff University of Vermont
    University of Vermont ScholarWorks @ UVM Graduate College Dissertations and Theses Dissertations and Theses 2009 Exploring Unique Aspects of Apicomplexan Cell Biology Using Molecular Genetic and Small Molecule Approaches Whittney Dotzler Barkhuff University of Vermont Follow this and additional works at: https://scholarworks.uvm.edu/graddis Recommended Citation Barkhuff, Whittney otzD ler, "Exploring Unique Aspects of Apicomplexan Cell Biology Using Molecular Genetic and Small Molecule Approaches" (2009). Graduate College Dissertations and Theses. 15. https://scholarworks.uvm.edu/graddis/15 This Dissertation is brought to you for free and open access by the Dissertations and Theses at ScholarWorks @ UVM. It has been accepted for inclusion in Graduate College Dissertations and Theses by an authorized administrator of ScholarWorks @ UVM. For more information, please contact [email protected]. EXPLORING UNIQUE ASPECTS OF APICOMPLEXAN CELL BIOLOGY USING MOLECULAR GENETIC AND SMALL MOLECULE APPROACHES A Dissertation Presented by Whittney Dotzler Barkhuff to The Faculty of the Graduate College of The University of Vermont In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Specializing in Cell and Molecular Biology May, 2009 Accepted by the FacuIty of the Graduate College, The University of Vermont, in partial fulfillment of the requirements for the degree of Doctor of Philosophy, specializing in Cell and Molecular Biology. Thesis Examination Committee: fl Advisor V<Q& Chairperson &(&53mhddL Associate Dean, Graduate College Patricia A. S tokowski, PhD December 19,2008 ABSTRACT The Phylum Apicomplexa contains a number of devastating pathogens responsible for tremendous human suffering and mortality. Among these are Plasmodium, which is the causative agent of malaria, Cryptosporidium, which causes diarrheal illness in children and immuncompromised people, and Toxoplasma gondii, which causes congenital defects in the developing fetus and severe disease in immunocompromised people.
    [Show full text]
  • Molecular Phylogeny of Noctilucoid Dinoflagellates (Noctilucales
    ARTICLE IN PRESS Protist, Vol. 161, 466–478, July 2010 http://www.elsevier.de/protis Published online date 26 February 2010 ORIGINAL PAPER Molecular Phylogeny of Noctilucoid Dinoflagellates (Noctilucales, Dinophyceae) Fernando Go´ meza,1, David Moreirab, and Purificacio´ nLo´ pez-Garcı´ab aMarine Microbial Ecology Group, Universite´ Pierre et Marie Curie, CNRS UMR 7093, Laboratoire d’Oce´ anographie de Villefranche, Station Zoologique, BP 28, 06230 Villefranche-sur-Mer, France bUnite´ d’Ecologie, Syste´ matique et Evolution, CNRS UMR 8079, Universite´ Paris-Sud, Batimentˆ 360, 91405 Orsay Cedex, France Submitted September 2, 2009; Accepted December 13, 2009 Monitoring Editor: Michael Melkonian The order Noctilucales or class Noctiluciphyceae encompasses three families of aberrant dinoflagellates (Noctilucaceae, Leptodiscaceae and Kofoidiniaceae) that, at least in some life stages, lack typical dinoflagellate characters such as the ribbon-like transversal flagellum or condensed chromosomes. Noctiluca scintillans, the first dinoflagellate to be described, has been intensively investigated. However, its phylogenetic position based on the small subunit ribosomal DNA (SSU rDNA) sequence is unstable and controversial. Noctiluca has been placed either as an early diverging lineage that diverged after Oxyrrhis and before the dinokaryotes -core dinoflagellates- or as a recent lineage branching from unarmoured dinoflagellates in the order Gymnodiniales. So far, the lack of other noctilucoid sequences has hampered the elucidation of their phylogenetic relationships to other dinoflagellates. Furthermore, even the monophyly of the noctilucoids remained uncertain. We have determined SSU rRNA gene sequences for Kofoidiniaceae, those of the type Spatulodinium (=Gymnodinium) pseudonoctiluca and another Spatulodinium species, as well as of two species of Kofoidinium, and the first gene sequence of Leptodiscaceae, that of Abedinium (=Leptophyllus) dasypus.
    [Show full text]
  • Toxoplasma Gondii: Further Studies on the Subpellicular Network
    706 Mem Inst Oswaldo Cruz, Rio de Janeiro, Vol. 104(5): 706-709, August 2009 Toxoplasma gondii: further studies on the subpellicular network Leandro Lemgruber1, John A Kloetzel2, Wanderley de Souza1,3, Rossiane C Vommaro1/+ 1Laboratório de Ultraestrutura Celular Hertha Meyer, Centro de Ciências da Saúde, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Cidade Universitária Bl. G, 21941-902 Rio de Janeiro, RJ, Brasil 2Department of Biological Sciences, University of Maryland Baltimore County, Baltimore, Maryland, USA 3Diretoria de Programas, Instituto Nacional de Metrologia, Normalização e Qualidade Industrial-INMETRO, Rio de Janeiro, RJ, Brasil The association of the pellicle with cytoskeletal elements in Toxoplasma gondii allows this parasite to maintain its mechanical integrity and makes possible its gliding motility and cell invasion. The inner membrane complex (IMC) resembles the flattened membrane sacs observed in free-living protozoa and these sacs have been found to associate with cytoskeletal proteins such as articulins. We used immunofluorescence microscopy to characterise the presence and distribution of plateins, a sub-family of articulins, in T. gondii tachyzoites. A dispersed labelling of the whole protozoan body was observed. Electron microscopy of detergent-extracted cells revealed the presence of a network of 10 nm filaments distributed throughout the parasite. These filaments were labelled with anti-platein antibodies. Screening the sequenced T. gondii genome, we obtained the sequence of an IMC predicted protein with 25% identity and 42% similarity to the platein isoform alpha 1 present in Euplotes aediculatus, but with 42% identity and 55% similarity to that found in Euglena gracilis, suggesting strong resemblance to articulins.
    [Show full text]